Los Angeles Clippers co-owner Shelly Sterling is mounting a hurried sale of the team she and her husband have owned for 33 years and could name a prospective new owner of the NBA franchise by the end of the week, a person familiar with the situation said.

The co-founder of investment bank Guggenheim Partners and its president are helping billionaire media executive David Geffen put together a group to bid on the Los Angeles Clippers.

Guggenheim said in a statement on Wednesday that co-founder and Chief Executive Officer Mark Walter and President Todd Boehly are joining Geffen's existing group of bidders, which includes television icon Oprah Winfrey and Oracle Chief Executive Officer Larry Ellison.

Clippers owner Donald Sterling, banned from the National Basketball Association for racist remarks, has handed controlling interest in his team to his wife Shelly Sterling, the co-owner. She began negotiating with the league to sell the club, Reuters reported on Friday, citing sources.

Guggenheim said in a statement that the two top executives were teaming up with Geffen to put together a bid, but that the bank itself was not officially involved in the process.

"Guggenheim is not involved in any way," a spokesman wrote in an e-mail. "Mark Walter and Todd Boehly are working with David Geffen and others to put together a bid to buy the Clippers."

Bids are due at 5 p.m. EST on Wednesday, according to a person with knowledge of the bidding process. A decision could be made by the end of the week.

In 2012, Walter headed a group including basketball great Magic Johnson that bought the LA Dodgers baseball team for $2.15 billion. Johnson has said he would likely join the bid if his Guggenheim partners made an offer.

Ressler met with Clippers co-owner Shelly Sterling at a Malibu restaurant last weekend to discuss a potential bid, according to the source with knowledge of the bidding process.

Representatives for Ballmer and Ressler could not be reached immediately.

Sterling is rushing to sell the team long headed by her husband, Donald, in an attempt to beat a deadline of next Tuesday, when owners of the 30 pro basketball teams will be asked to strip control of the team from both of the Sterlings, after Donald Sterling’s racially-charged remarks about blacks.

The developments in the NBA’s biggest ownership crisis came on the same day that a defiant Sterling lashed out at what he called the league’s “illegal termination process.” In a cover letter to the 29-page document, obtained by The Times, Sterling said he had already received offers “in excess of $2.5 billion” for his team. In his response, he criticized the NBA for insisting on his ouster for what he deemed a single illegally-recorded conversation of what he deemed “a lover’s quarrel.”

The series of events suggested a potentially quick resolution to a controversy that appeared as if it might drag on for months or more, though people familiar with the situation cautioned that the sale is far from complete and must be approved by the NBA’s other owners.

The magnitude of the Clippers deal and the field of prospective owners had begun to crystallize Tuesday, with one likely bidder dismissing the $2.5 billion price tag but saying the team would likely go for more than $1 billion. That would be the highest sale price in NBA history, topping the $550 million theMilwaukee Bucks were sold for in April.

One new buyers alliance already came together in recent days when Chicago-based Guggenheim Partners, which bought the Dodgers two years ago for more than $2 billion, agreed to work with a trio of billionaires who previously said they would launch their own bid for the Clippers — Oracle software co-founder Larry Ellison, entertainment magnate David Geffen and mega-entrepreneur Oprah Winfrey.

Another partnership included three principals who have significant ties to major league sports — Tony Ressler, the Los Angeles-based co-founder of the investment firm Ares Management and a minority owner of baseball’s Milwaukee Brewers; Bruce Karsh, co-founder of Oaktree Capital Management and a minority owner of the NBA’s Golden State Warriors and Grant Hill, a one-time NBA all-star who finished his career with the Clippers.

Also expected to bid for the team after meeting with Shelly Sterling on Sunday is Steve Ballmer, who stepped down as chief executive of Microsoft in February after leading the software company for 14 years.

Ballmer last year joined a group, led by hedge fund manager Chris Hansen, to bid on the Sacramento Kings and intended to move the team to Seattle. NBA owners voted to reject the proposed move.

Ballmer said in an interview with the Wall Street Journal that, if he succeeded in his new bid, he would not attempt to move the Clippers. He said the team would lose much of its value by leaving L.A.

One of the bidders, who requested anonymity because of the sensitivity of negotiations, said Tuesday the process would move quickly. “The bids are due Thursday afternoon at 2 p.m.” the bidder said. “We will probably know who bought the team by Friday.”

Any deal would be contingent on the approval of three-quarters of the NBA’s owners. People familiar with the league’s position said the NBA would continue with the process of removing the Sterlings at a hearing next Tuesday in New York, to keep the pressure on for completion of the sale.

Michael Bass, the NBA’s chief spokesman, reiterated the comments of Commissioner Adam Silver last week: “It would be a preferred outcome if the Sterlings were to voluntarily transfer 100% of the ownership in the team to new owners, rather than to have their ownership in the team terminated.”

Donald Sterling’s wife of 58 years has held half of the team through a family trust but only recently came to the forefront when her husband said he had turned over control to her and would let her attempt to sell the team. Donald Sterling remains the controlling owner of the team in the eyes of the NBA, but league officials said they would not stand in the way of any legitimate sale.

The Clippers had just concluded their most successful regular season and were in the playoffs when Sterling’s racially-charged remarks against African-Americans were posted on the celebrity website TMZ.

The comments unleashed fury among fans, a threatened boycott by players and the flight of sponsors. Silver fined the owner $2.5 million (which Sterling refused to pay), placed a lifetime ban on him and urged owners to force him out of the league.

Much of the defense that Sterling emailed to the NBA hours before a midnight deadline Tuesday centered on his complaint that he was being taken to task for remarks he made in private to V. Stiviano.

Stiviano, 31, was a frequent companion and some-time assistant to the 80-year-old Sterling. Stiviano has described her relationship with the elderly real estate magnate as platonic, akin to a father and daughter. But Sterling has made clear he was enamored with her and depicted his statements as the result of a “lovers’ quarrel.”

Stiviano has said she routinely made recordings of Sterling and at times used them to try to coach him to be more polite. She said he knew about a recording she made in September of 2013, when they argued about an Instagram photo she took with Lakers legend Magic Johnson.

Sterling reiterated in his written defense Tuesday, that he did not know Stiviano was recording him. He called the audio “illegally recorded.” California law prohibits recording an individual without their permission.

The response went on to claim Sterling was “distraught” when he made the statements, because Stiviano told him she planned to bring “four gorgeous black guys to the game” and that those strong feelings should be viewed by the NBA as a mitigating factor.

“This was an argument between a jealous man and the woman he loved that should never have left the privacy of the living room,” the response said.

The document further claims Sterling is hindered from conducting his own investigation of the matter because he’s “locked out of his office at Staples Center" — part of his ban from the league. The response said it did not “believe a court in the United States of America will enforce the draconian penalties imposed on Mr. Sterling in these circumstances. … Indeed, we believe that preservation of Mr Sterling’s constitutional rights requires that these sham proceedings be terminated in Mr. Sterlings favor.”

Donald Sterling is expected to launch what could be a long and contentious legal battle with the NBA over his ownership of the Clippers without the support of the big, politically connected law firm that has been with him for more than three decades.

Magic Johnson on Tuesday evening said Donald Sterling's comments about minorities shows that he's "living in the Stone Ages," and he advised the embattled billionaire to enjoy the rest of the life and forget about trying to retain ownership of the Clippers.